The present invention relates to a machine for exercising or testing muscles of the lower trunk such as the lumbar or abdominal muscles. The machine is of the type disclosed in my prior copending application Ser. No. 07/060,679 identified above. Another machine for exercising such muscles is disclosed in U.S. Pat. No. 4,462,252 to Smidt et al, issued July 31, 1984. The present invention also relates to a method utilizing the machine for exercising or testing the lumbar or abdominal muscles.
In machines such as identified above, the exerciser is seated with his pelvis restrained against movement, and in the case of lumbar exercise, the lumbar muscles are exerted to extend the spine rearwardly to move a movement arm about a horizontal axis. The forces of the lumbar muscles are transmitted to the movement arm through a resistance pad engaged by an upper back portion of the exerciser. A resistance is connected to the movement arm to load the movement arm against the forces applied by the muscles. The torque applied by the muscles to the movement arm may be measured to determine the work capacity of the exerciser. In another mode of the machine, the movement arm is fixed so that the static strength of the muscles may be tested.
An object of the present invention is to provide certain novel improvements to a machine of the type described in order to facilitate the operation and accuracy thereof. Included herein is the provision of such a machine having novel apparatus for anchoring the pelvis against movement. Also included is provision for detecting any unwanted movement of the pelvis during exercise.
Further included within the objects of the present invention is such a machine having novel apparatus for accurately measuring the force or torque applied to the movement arm by the muscles being tested.
Another object of the present invention is to provide such a machine of the type described having novel apparatus of counterbalancing the torso mass of the exerciser so that it will not affect the accuracy of the measurements of torque or force applied by the muscles being tested or exercised.
A further object of the present invention is to provide such a machine of the type described having novel apparatus for varying the range of movement of the movement arm during an exercise mode or for placing the movement arm in different angular fixed positions for testing the static strength of the muscles in each of those positions.
A still further object of the present invention is to provide a novel method for testing the static strength and work capacity of the lumbar or abdominal muscles with little, if any, risk of injury to these muscles.